WRENTHAM — For one last time, it was St. John’s Prep’s Tristan Shelgren vs. Newton North’s Andrew Mah.

The seniors have been at the top of every cross-country race they have participated in this fall. On Saturday at the Wrentham Developmental Center, Shelgren edged Mah for the victory, as he’d done twice previously on the same course this year.

The only difference, however, was Saturday’s 3.1-mile race was for the All-State Division 1 championship. The University of North Carolina-bound Shelgren traversed the course in 15 minutes 15 seconds. Mah finished second at 15:37.

“We’ve been rivals since freshman year,’’ Shelgren said. “It’s just a perfect scenario.’’

Shelgren had just the slightest of leads at the 2-mile mark. But as the duo climbed the first hill after the 2 miles, Shelgren’s lead began to expand into the insurmountable advantage that he finished with.

St. John’s Shrewsbury placed first as a team, with 81 points, behind the fourth- and fifth-place finishes of Patrick Craemer and Joshua Rahn. Lowell (104 points) and Wellesley (116 points) rounded out the top three.

In the Division 2 race, the individual title was won by a Newburyport runner for the second consecutive year. After watching his former teammate Jack Carleo claim the award last season, Sam Acquaviva now has some hardware of his own. The senior finished in 15:58 to beat out Westwood’s Zach Conant (16:06) for first place.

“It feels great to win,’’ Acquaviva said. “I’ve been training with my teammates, they’ve been a really big help.’’

He added that Jack Carleo and Nick Carleo, who won back-to-back state titles at Newburyport in 2013-14, were in attendance to cheer him on. Acquaviva said prior to the race they talked about everything but cross-country, which gave Acquaviva a chance to get his mind off the task in front of him.

Parker Charter won the team championship with 90 points, followed by Pentucket (95) and Hopedale (98).

Grace Connolly repeats

Just as she has done all fall, Natick junior Grace Connolly bolted to the front of the pack at the sound of the gun, gradually separating herself from the field. By the 2-mile mark, there was no one in sight. Connolly cruised to her second straight girls’ Division 1 All-State title, completing the 3.1-mile course at the Wrentham Developmental Center in 17 minutes, 50.18 seconds.

“I just really wanted to push myself and charge the hills,’’ said Connolly. “My goal for this season was to win All-States and now it’s all about preparation for Foot Locker Regionals [in New York] next weekend.’’

Connolly was neck and neck in the first 800 meters with Milton senior Bridget Mitchell, who, along with her teammates, moved up to Division 1 from D2 this season.

But with each rolling hill, Connolly’s lead expanded.

Mitchell finished third at 18:08.39 behind Wellesley junior Maggie Donahue (18:07.53).

“It’s super exciting having Bridget [Mitchell] in D1 because it’s just one more person to push me,’’ Connolly said. “It made me a little more nervous but it was good nerves. It gives the pressure to push it even harder and finish even stronger.’’

Concord-Carlisle (116 points) captured the Division 1 team title, nosing out Wellesley (122) and Tewksbury (143).

In the Division 2 race, Littleton junior Sarah Roffman (18:12.40) used a strong finishing kick to edge Nauset’s Madaket Nobili (18:26.98) and Eve Feuerbach of Manchester Essex (18:26.73).

“It’s definitely something that I’ve had to get used to,’’ said Roffman, who is running cross-country for the first time. “We’ve done so many workouts where we run up a hill but you have to push yourself to keep going as fast as possible. Our course has a mile uphill on it, so that’s something we take advantage of.’’

Her twin sister, Kaitlyn (18:40), finished seventh, and Littleton was sixth overall.

Mount Greylock (87) won the D2 title, Nauset (125) was second, and Lenox Memorial (126) third.

All-State Cross-Country Championships

at Wrentham Developmental Center (3.1 miles)

Boys’ Division 1 individual

1. Tristan Shelgren, St. John’s Prep, 15:15.82; 2. Andrew Mah, Newton North, 15:37.94; 3. Lucas Aramburu, Brookline, 15:45.86; 4. Patrick Craemer, Saint John’s Shrewsbury, 15:48; 5. Joshua Rahn, Saint John’s Shrewsbury, 15:52.28; 6. Ryan Oosting, Arlington, 15:59.41; 7. Cameron McLeod, Needham, 15:59.79; 8. Nasir Gibson, Lowell, 16:00.34; 9. Colin Fitzpatrick, Lowell, 16:00.74; 10. Gabriel Medina, West Springfield, 16:01.96; 11. Thomas Lingard, Lexington, 16:03.32; 12. Kalin Petrov, Mansfield, 16:03.45; 13. Ian Horsbugh, Newton North, 16:05.50; 14. Mike Griffin, King Philip, 16:06.53; 15. Timothy McClure, Concord-Carlisle, 16:06.89.

Boys’ Division 1 teams

1. St. John’s Shrewsbury, 81; 2. Lowell, 104; 3. Wellesley, 116; 4. Concord-Carlisle, 149; 5. Newton North, 151.

Boys’ Division 2 individuals

1. Sam Acquaviva, Newburyport, 15:58.81; 2. Zach Conant, Westwood, 16:06.77; 3. Nico Agosta, Parker Charter, 16:09.30; 4. Brandon Hall, Hopedale, 16:12.05; 5. Steven O’Driscoll, Norwell, 16:17.24; 6. Trevor Mungeam, Douglas, 16:17.97; 7. Ethan Matthews, Ayer Shirley, 16:18.95; 8. Kellen Waters, Ipswich, 16:20.32; 9. Sean Kay, Arlington Catholic, 16:20.55; 10. Quinn Cantrill, Parker Charter, 16:21.39; 11. Andrew Corbett, Norwell, 16:27.40; 12. Peter Lopata, Pentucket, 16:36.64; 13. Zack Bergeron, Blackstone Valley, 16:41.14; 14. Jake Luongo, Stoneham, 16:41.81; 15. Will Kenney, Manchester Essex, 16:42.37.

Boys’ Division 2 teams

1. Parker Charter, 90; 2. Pentucket, 95; 3. Hopedale, 98.